Media captionKeith Vaz: ''This is a huge number of names, more than we expected''

The names of 1,444 former and serving police officers have been passed to the Independent Police Complaints Commission as part of its investigation into the Hillsborough disaster.

Home Affairs Committee chairman Keith Vaz told MPs the "huge number" had been revealed to him in a letter from South Yorkshire Police's chief constable.

The government said the number showed the "enormity" of the investigation.

But the police watchdog probe would be "thorough and wide-ranging", it added.

MPs were debating the Independent Hillsborough Panel Report, which last month found police and emergency services had made "strenuous attempts" to deflect the blame for the disaster - in which 96 people died - on to fans.

The independent panel revealed 164 police statements had been altered - 116 of them to remove or change negative comments about the policing of the FA Cup semi-final between Liverpool and Nottingham Forest at the Sheffield stadium.

The panel also found that 41 of the 96 who had died had had the "potential to survive", and the attorney general last week asked the High Court to consider ordering fresh inquests into the deaths.

The Independent Police Complaints Commission (IPCC) and the director of public prosecutions are both conducting inquiries into possible crimes committed by police.

The IPCC is looking at whether there was a criminal cover-up by South Yorkshire Police of failings by the force.

Mr Vaz said the number of police officers who may need to be investigated was more than had been expected and it was essential the commission had enough money to pursue its inquiries.

Shadow home secretary Yvette Cooper said the investigation was "beyond the scale of anything the IPCC has done before" and required powers, such as compelling former and serving officers to be interviewed, which it did not have.

Home Secretary Theresa May said she "remained committed to ensuring it has all the resources and powers it needs to carry out its investigations thoroughly, transparently and exhaustively".

She confirmed she would work with Labour to see if new laws were needed to compel former officers to co-operate with the IPCC.

"This includes proposals to require current and ex-police officers who were maybe witnesses to a crime to attend an interview, and whether this might require fast-track legislation," she added.

Shadow transport secretary Maria Eagle - a Merseyside MP - told MPs that West Yorkshire's Chief Constable, Sir Norman Bettison, an officer for the South Yorkshire force at the time, attempted to "fit-up" Liverpool football fans after the disaster.

She said had received a letter from John Barry, originally sent in 1998 to a solicitor working on behalf of the bereaved families, in which Mr Barry claims Sir Norman told him, just weeks after the event, that the police were "trying to concoct a story that all the Liverpool fans were drunk".

Ms Eagle has previously called for Sir Norman to be suspended following reports - being investigated by the Independent Police Complaints Commission - that he provided misleading information after the Hillsborough tragedy.